diff --git a/apps/web/cypress/e2e/sidebar.cy.ts b/apps/web/cypress/e2e/sidebar.cy.ts
index a7d20ab..2d69946 100644
--- a/apps/web/cypress/e2e/sidebar.cy.ts
+++ b/apps/web/cypress/e2e/sidebar.cy.ts
@@ -58,4 +58,26 @@ describe("Sidebar — settings menu and account menu", () => {
     cy.visit("/foyer");
     cy.url().should("include", "/parametres/foyer");
   });
+
+  it("collapses to an icon-only rail and back, persisting the choice across reloads", () => {
+    cy.visit("/");
+
+    cy.get(".app-sidebar").should("not.have.class", "collapsed");
+    cy.contains("nav a", "Planning").should("be.visible");
+
+    cy.get(".app-sidebar__collapse-toggle").click();
+    cy.get(".app-sidebar").should("have.class", "collapsed");
+    // The label text hides (not removed from the DOM — still there for the
+    // `title` tooltip/accessibility), while the link itself stays visible,
+    // icon-only.
+    cy.contains("span.label", "Planning").should("exist").and("not.be.visible");
+    cy.get("nav a[title='Planning']").should("be.visible");
+
+    cy.reload();
+    cy.get(".app-sidebar").should("have.class", "collapsed");
+
+    cy.get(".app-sidebar__collapse-toggle").click();
+    cy.get(".app-sidebar").should("not.have.class", "collapsed");
+    cy.contains("nav a", "Planning").should("be.visible");
+  });
 });